Valve for controlling a fluid medium flowing under pressure

ABSTRACT

A valve 1 for controlling a fluid medium flowing under pressure comprises an inlet opening 6 and an outlet opening 12 as well as an inlet member 4 having the medium flowing axially therethrough and a sleeve-shaped control member 13 axially displaceable between a closed and an open position relative to the inlet member 4, whereby in the closed position the outlet opening 12 is closed and in the open position the outlet opening 12 is opened. In addition, a first radially projecting, elastic sealing ring 24b is provided and a first annular sealing edge 25 which is adapted to be pressed sealingly against the first sealing ring 24b in a closed position of the control member 13. The displaceable control member 13 is enclosed by a valve housing 2 and the space between control member 13 and valve housing 2 is acted upon by the fluid medium flowing under pressure so that essentially no resulting pressure in axial direction is present at the control member and therefore the control member 13 is displaceable without any appreciable expenditure of force. A second radially projecting, elastic sealing ring 26b is provided in axial spaced relation to the first sealing ring 24b. A second annular sealing edge 27 is adapted to be pressed sealingly against the second sealing ring 26b in a closed position of the control member 13.

The invention relates to a valve for controlling a fluid medium flowingunder pressure, comprising inlet openings and outlet openings, an inletmember having the medium flowing axially therethrough, a sleeve-shapedcontrol member axially displaceable between a closed and an openposition in relation to the inlet member, a first radially projecting,elastic sealing ring and a first annular sealing edge which is adaptedto be pressed sealingly against the first sealing ring in the closedposition of the control member, whereby the displaceable control memberis enclosed by a valve housing and the space between the control memberand valve housing is acted upon with the fluid medium flowing underpressure so that essentially no resulting pressure in axial direction ispresent at the control member and therefore the control member isdisplaceable without any appreciable expenditure of force, a secondradially projecting, elastic sealing ring is provided in axial spacedrelation to the first sealing ring and a second annular sealing edge isadapted to be pressed sealingly against the second sealing ring in theclosed position of the control member.

A valve of this type is known from U.S. Pat. No. 3,654,950. The firstand second sealing rings provided therein are U-shaped and formed from aflexible material with two legs, between which a spring is inserted.Shortly before reaching the closed position, the one leg is pressedforcibly against one of the first and second annular sealing edges dueto a differential pressure. As a result of this strong pressing action,there is, of necessity, a relatively large areal contact between sealingring and sealing edge so that a relatively large force must be appliedwhen opening the valve.

When such valves are used in mining and underground workings, they arecontrolled and supplied from a central control device via data lineswhich are known per se. Since only small electrical currents ought toflow in these data lines in view of a possible risk of explosion, thesupply to the valves presupposes a low intrinsic current requirement andtherefore as small an actuating force, in particular opening force, aspossible. The known valve does, however, have a high intrinsic currentrequirement due to the large opening force required.

The object of the invention is to improve a valve of the generic typesuch that it is easy to open with a more or less infinitesimalexpenditure of force, whereby the valve is also intended to allow, inparticular, the control of fluid media flowing under very high pressure.

The object is accomplished by the invention, in a valve of the generictype, in that the first and second annular sealing edges are designed tobe relatively sharp and like knife edges and in a closed position of thevalve form a sealing region in the form of a circular line between thefirst and second sealing rings, on the one hand, and the first andsecond sealing edges, on the other hand.

The following description comprising the preferred embodiments of theinvention serves to explain the invention further in conjunction withthe attached drawings.

In the drawings:

FIG. 1 is a sectional illustration of an inventive valve for controllinga fluid medium flowing under pressure in a closed position;

FIG. 2 is a sectional illustration of the valve from FIG. 1 in an openposition;

FIG. 3 is an enlarged, sectional, individual illustration of a tubularinlet member and a sleeve-shaped control member axially displaceablethereon in a closed position;

FIG. 4 is a sectional view of a second embodiment of an inventive valvein a closed position;

FIG. 5 is a sectional view of a third embodiment of an inventive valvein an open position;

FIG. 6 is a sectional view of a fourth embodiment of an inventive valvein an open position;

FIG. 7 is a sectional view of a fifth embodiment of an inventive valvein an open position.

A valve 1 illustrated in FIG. 1 in a closed position has a valve housing2, preferably made of metal, in which an axial valve bore 3 is located.A tubular, likewise preferably metal inner or inlet member 4 is arrangedin the valve bore 3 and an inlet opening 6 provided with a thread isprovided at one end of this inlet member and open outlet regions 7 arearranged at its other end. The tubular inlet member 4 is rigidly andsealingly connected to the valve housing 2 by means of screws 8. Inaddition, a cover plate 9 is secured to the valve housing 2 by means ofscrews 11 and an outlet opening 12 likewise provided with a thread islocated in this cover plate.

The tubular inlet member 4 is surrounded by a sleeve-shaped outer orcontrol member 13, preferably made of metal, which is arranged for axialdisplacement on the tubular inlet member 4.

A groove 14 is arranged in the outer circumference of the sleeve-shapedcontrol member and a projection 16 engages in this groove as drivemember. The projection 16 is connected in one piece to a nut 17 whichfits onto a threaded rod 18. A shaft 19 is rigidly connected to thethreaded rod 18. Rotation of this shaft causes an axial movement of thenut 17 and the projection 16 so that the sleeve-shaped control member 13is displaced axially in relation to the tubular inlet member 4 and,thus, the valve 1 is switched from its closed into its open position andvice versa. A small electromotor which is not illustrated and has a lowcurrent consumption can, for example, be connected to the shaft 19. Itis also possible to actuate the valve 1 by hand.

The entire interior space 21 of the valve (valve bore 3), including thespace 22, in which the threaded rod 19 with the associated nut 17 arelocated, is constantly filled--in particular in the open position--withthe fluid medium under pressure, e.g. water, oil or the like. In thisway, the sleeve-shaped control member 13 is entirely enclosed by mediumunder pressure and can be displaced relative to the inlet member 4 moreor less without any expenditure of force.

In the closed position of the valve 1 shown in FIG. 1, the inlet opening6 is sealingly closed in relation to the outlet opening 12. Thesleeve-shaped control member 13 is pushed into the closed position onthe tubular inner member 4--to the right in FIG. 1.

In FIG. 2, the valve 1 is illustrated in its open position so that thefluid medium under pressure passes from the inlet opening 6 via theinterior space 21 and the outlet regions 7 into the outlet opening 12.The sleeve-shaped control member 13 is thereby displaced along thetubular inlet member 4 into an open position--to the left in FIG. 2.

FIG. 3 shows an enlarged individual illustration in a sectional view ofthe tubular inlet member 4 and the sleeve-shaped control member 13axially displaceable thereon in a closed position of the valve 1. Anannular groove 24a is arranged at the outer circumference of the inletmember 4 and a first sealing ring 24b which projects radially somewhatbeyond the outer circumference of the inlet member 4 and has anessentially rectangular or circular cross section (O-ring seal) isinserted into this groove. A first annular sealing edge 25 on thesleeve-shaped control member 13 is associated with and adjacent thegroove 24a and the sealing ring 24b and in a closed position of thevalve is brought into engagement on the sealing ring 24b. The groove24a, the sealing ring 24b and the sealing edge 25 are arranged in thevicinity of the inlet opening 6 of the valve.

An annular groove 26a arranged on the inner circumferential surface ofthe sleeve-shaped control member 13 is located in the vicinity of theoutlet opening 12 of the valve 1 and a second sealing ring 26b (O-ringseal) which projects somewhat beyond the inner circumferential surfaceis inserted into this groove. A second sealing edge 27 arranged in thevicinity of the groove 26a and the sealing ring 26b at the outercircumferential surface of the tubular inlet member 4 engages on thesealing ring 26b in a closed position of the valve 1 essentially at thesame time as the sealing edge 25 also meets the sealing ring 24b. Thesealing edges 25, 26 engage sealingly on the sealing rings 24b, 26balong circular lines, i.e. with relatively small areas. Intermediatespaces 21a are formed between the tubular inlet member 4 and thesleeve-shaped control member 13 and these spaces are filled with thefluid medium under pressure in a closed position due to the lack of aseal.

The manner in which the valve functions is apparent from FIGS. 1 and 2in conjunction with FIG. 3. In an open position of the valve 1 (FIG. 2),the sleeve-shaped control member 13 is axially displaced relative to thetubular inlet member 4--to the left in FIG. 2--such that the first andsecond sealing edges 25, 27 are removed from the first and secondsealing rings 24b, 26b which enables the fluid medium flowing underpressure to flow out through the outlet regions 7 and the outlet opening12.

In a closed position (FIGS. 1 and 3), the sealing edges 25, 27 engageessentially simultaneously on the sealing rings 24b, 26b locatedrespectively opposite them due to axial displacement of thesleeve-shaped control member 13 on the tubular inlet member 4--to theright in FIG. 2--while the medium which is located continuously in thespaces 21a, flows under pressure and surrounds the control member 13 onall sides enables the control member 13 to be displaced almost withoutany expenditure of force.

During the closing procedure, a pressure is built up in the spaces 21awhich presses the two sealing rings 24b, 26b against the two relativelysharp, knife-like sealing edges 25, 27, whereby the sealing rings aresomewhat deformed and form respective sealing regions in the form ofcircular lines at the sealing edges 25, 27. In addition, the sealingrings 24b, 26b are pressed against the sealing edges 25, 27 by theflowing medium due to a suction effect in the space located respectivelybehind them. In this position, the valve 1 does not close the inletopening 6 in relation to the outlet opening 12.

The valve 1 can also be opened easily, i.e. without any appreciableexpenditure of force, since the two sealing edges 25, 27 form at the twosealing rings 24b, 26b only respective sealing regions in the form ofcircular lines which can be separated from the sealing rings by means ofonly a small expenditure of force even at high pressures of the flowingfluid medium.

In this way, it is possible to open and close the valve with an almostinfinitesimal expenditure of force. The valve 1 can, in addition, beheld in a closed as well as in an opened state without any expenditureof force. Consequently, the valve can be held in the closed or openedstate without any motor drive and without drive current since aservomotor required for the opening and closing need not be actuatedonce the open or closed position is reached. The valve is thereforeoperated completely "current-free" in the opened or closed state andonly very small servomotors and minimal currents are necessary for theopening and closing procedure.

Instead of the sealing rings 24b, 26b with a circular cross section,sealing rings having, for example, square, semicircular, triangular oroval cross sections are also possible.

Furthermore, the sealing rings 24b, 26b which project radially somewhatbeyond the tubular inlet member or beyond the sleeve-shaped controlmember 13 can also be replaced by plastic projections which are rigidlyarranged on the inlet member 4 or the control member 13 and againstwhich the sealing edges 25, 27 which are preferably metallic and locatedrespectively opposite these projections come to rest.

Moreover, a good sealing effect can also be attained with two metaledges or metal surfaces which abut directly on one another when metalprojections are used instead of the plastic projections.

The invention provides for a valve which can be produced with lowproduction costs--no exact tolerances are, for example, required--,which can be directly actuated more or less without any force, which canbe operated current-free in each switching position (open or closedposition) and which is also sealed against very high pressures. Thevalve is, therefore, especially suitable for use in mining orunderground workings. In addition, it is possible to use it in drinkingwater supply as well as in gas and compressed air systems.

FIG. 4 shows a modified, second embodiment of a valve, in which theoutlet regions 7 are modified in comparison with FIGS. 1-3 and thesealing edge 27 is not formed on the stationary inner member 4 as inFIGS. 1-3 but on a projecting part 10 of the likewise stationary coverplate 9. The outlet regions 7 are located between the part 10 and thecover plate 9. As for the rest, the valve according to FIG. 4 functionsin the same way as that according to FIGS. 1-3.

In the embodiments according to FIGS. 1-3 and 4 a stationarily held ringseal 24b interacts with a respective movable sealing edge 25 provided onthe control member 13 and a ring seal 26b movable together with thecontrol member 13 interacts with a stationary sealing edge 27, wherebythe stationary sealing edge 27 is formed in FIGS. 1-3 on the inletmember 4 and in the embodiment according to FIG. 4 on the part 10 of thecover plate 9.

The third embodiment of a valve illustrated in an open position in FIG.5 differs from the two embodiments according to FIGS. 1-3 and 4 in thatthe first sealing ring 24b is formed on the outer side of the controlmember 13 and is movable together with it. The sealing ring 24binteracts with a first sealing edge 25 stationarily formed on the innerside of the valve housing 2.

The second sealing ring 26b is stationarily arranged on the projectingpart 10 of the cover plate 9 and interacts with a second sealing edge 27formed on the displaceable control member 13 at its end. A washer 31which is firmly held in the part 10 by a screw 32 holds the sealing ring26b in an associated annular groove in the part 10. As for the rest, theembodiment according to FIG. 5 functions in the same manner as theembodiments according to FIGS. 1-4.

In the additional embodiments of valves, as illustrated in an openposition in FIGS. 6 and 7, parts which correspond with one another havebeen designated with the same reference numerals as in FIGS. 1-5.However, whereas in FIGS. 1-5 a stationary sealing ring (e.g. thesealing ring 26b in FIG. 5) and a sealing ring movable with the controlmember 13 (e.g. in FIG. 5 the sealing ring 24b) are provided each timeand these interact with respective movable or stationary sealing edges(in FIG. 5 the sealing edges 27 and 25, respectively), in theembodiments according to FIGS. 6 and 7 the first and second sealingrings 24b, 26b are arranged so as to be either stationary or movabletogether such that they interact with sealing edges 25, 27 which are,for their part, either movable together or stationary.

In FIG. 6, the first and second sealing rings 24b, 26b are held incorresponding annular grooves of the valve housing 2 and the part 10 ofthe cover plate 9, respectively, so as to be stationary, i.e.non-displaceable. These sealing rings 24b, 26b interact with controledges 25 and 27, respectively, which are formed on the control member 13in the illustrated manner and are movable together with it.

Finally, in the embodiment according to FIG. 7 first and second sealingrings 24b, 26b , which are formed on the control member 13 and movabletogether with it, interact with first and second sealing edges 25, 27,which are formed stationarily on the valve housing 2 and on theprojecting part 10 of the cover plate 9, respectively.

FIGS. 6 and 7 show the valve in an open position. The valve istransferred into a closed position in that the control member 13 isdisplaced each time to the right in these Figures until the sealingedges 25, 27 abut sealingly on the sealing rings 24b and 26b ,respectively. As for the rest, the embodiments according to FIGS. 6 and7 function in the same manner as the embodiments according to FIGS. 1-4.In particular, a projection 16 which is, for example, driven by a motorcan, in turn, engage in the groove 14 of the control member 13 in FIGS.5-7 as well. In the embodiments according to FIGS. 5-7 the controlmember 13 is guided only on one side in the inlet member 4. In thiscase, parts of the inner side of the valve housing 2 serve foradditional guidance of the control member 13.

Due to the different arrangement of the sealing rings 24a, 26a, there isa further difference between the embodiments according to FIGS. 1 to 4,on the one hand, and 5 to 6, on the other hand: In the embodimentsaccording to FIGS. 1 to 4, there is no connection between the inletopening 6 and the space 22 containing the drive member 16 in the closedstate of the valve because such a connection is prevented by the seal24a. In the embodiments according to FIGS. 5 to 6, on the other hand,such a connection does exist past the control member 13 in the closedstate of the valve, as can be easily verified on the basis of FIGS. 5 to7.

I claim:
 1. Valve (1) for controlling a fluid medium flowing underpressure, comprising inlet openings (6) and outlet openings, an inletmember (4) having the medium flowing axially therethrough, asleeve-shaped control member (13) axially displaceable between a closedand an open position in relation to the inlet member (4), a firstradially projecting, elastic sealing ring (24b) and a first annularsealing edge (25) adapted to be pressed sealingly against the firstsealing ring (24b) in the closed position of the control member (13),whereby the displaceable control member (13) is enclosed by a valvehousing (2) and the space between the control member (13) and valvehousing (2) is acted upon with the fluid medium flowing under pressureso that essentially no resulting pressure in axial direction is presentat the control member (13) and therefore the control member isdisplaceable without any appreciable expenditure of force, a secondradially projecting, elastic sealing ring (26b) is provided in axialspaced relation to the first sealing ring (24b) and a second annularsealing edge (27) is adapted to be pressed sealingly against the secondsealing ring (26b) in the closed position of the control member (13),characterized in that the first and second annular sealing edges (25,27) are designed to be relatively sharp and like knife edges and in aclosed position of the valve form a sealing region in the form of acircular line between the first and second sealing rings (24b, 26b), onthe one hand, and the first and second sealing edges (25, 27), on theother hand.
 2. Valve as defined in claim 1, characterized in that of thetwo sealing rings (24b, 26b) on the valve (1) one (24b) is designed tobe stationary and the other (26b) to be movable together with thecontrol slide (13), and a sealing edge (25) movable together with thecontrol slide (13) is associated with the stationary sealing ring (24b)and a stationary sealing edge (27) with the movable sealing ring (26b)(FIGS. 1-3; 4; 5).
 3. Valve as defined in claim 2, characterized in thatthe first sealing ring (24b) is formed stationarily on the inlet member(4), the first sealing edge (25) is formed on the displaceable controlmember (13), the second sealing ring (26b) on the displaceable controlmember (13) and the second sealing edge (27) stationarily on the inletmember (4) (FIGS. 1-3).
 4. Valve as defined in claim 2, characterized inthat the first sealing ring (24b) is formed stationarily on the inletmember (4), the first sealing edge (26) is formed on the displaceablecontrol member (13), the second sealing ring (26b) on the displaceablecontrol member (13) and the second sealing edge (27) stationarily on acover plate (9) connected to the valve housing (2) and enclosing theoutlet opening (12) (FIG. 4).
 5. Valve as defined in claim 2,characterized in that the first sealing ring (24b) is formed on thedisplaceable control member (13), the first sealing edge (25) on thevalve housing (2), the second sealing ring (26b) stationarily on a coverplate (9) connected to the valve housing (2) and enclosing the outletopening (2) and the second sealing edge (27) on the displaceable controlmember (13) (FIG. 5).
 6. Valve as defined in claim 1, characterized inthat the two sealing rings (24b, 26b) are formed stationarily on thevalve (1) and a sealing edge (25, 27) movable together with the controlslide (13) is associated with each sealing ring (24b, 26b) (FIG. 6). 7.Valve as defined in claim 1, characterized in that the two sealing rings(24b, 26b) are designed to be movable together with the control slide(13), and a stationary sealing edge (25, 27) is associated with eachsealing ring (24b, 26b) (FIG. 7).
 8. Valve as defined in claim 1,characterized in that in a space (21a) filled with fluid medium andlimited at its ends by the sealing rings (24b, 26b) the two sealingrings (24b, 26b) are adapted to be pressed sealingly against theirassociated sealing edges (25, 27) essentially simultaneously in theclosed position.
 9. Valve as defined in claim 1, characterized in thatthe sealing rings (24b, 26b) are arranged in circumferential grooves(24a, 24b) so as to protrude radially.
 10. Valve as defined in claim 1,characterized in that the sealing rings (24b, 26b) are O-rings having anat least partially round cross-sectional shape.
 11. Valve as defined inclaim 1, characterized in that the sealing rings (24b, 26b) are O-ringshaving an at least partially angular cross-sectional shape.
 12. Deviceas defined in claim 1, characterized in that the sealing rings (24b,26b) are designed as annular plastic projections.
 13. Device as definedin claim 1, characterized in that a groove (14) extending incircumferential direction is arranged in the outer circumferentialsurface of the sleeve-shaped control member (13), a drive member (16)for displacing the control member (13) engaging in said groove.